Unfortunately for Paul Wight, there's not a lot of other jobs the guy can do. He tried being an actor, and he tried being a boxer. Obviously boxing didn't work out for him, hence why he returned to the 'E. As far as acting goes, he doesn't have the natural ability that a lot of actors do. The only thing he has going for him is his size and strength, and that makes him a perfect fit for professional wrestling.
I feel that pro wrestling is what Mr. Wight was born to do, and he should do it for as long as he's able. I understand the argument that he has done everything there is do to in pro wrestling (won all the titles, played all the characters he could have, etc), but that shouldn't be a reason to quit the business. Big Show can still go in the ring just about as well as he always could, and I still enjoy watching him wrestle. I've only seen Big Show in person once (it was from the nosebleed section of The Palace in Detroit), when he was still with WCW as "The Giant". Even from my seat (which were waaaaay up in the upper deck), it was astounding to see how huge this guy is in person. Kevin Nash was in the ring at the time as well (I had gone to see WCW's "World War III" in 1998), but Big Show looked like he was a foot taller than Nash (I know he's not much bigger than Nash in real life). There's something about the guy that just screams "dominance", even if it doesn't come across that way on television. I think the main problem with his character nowadays is that WWE made him a joke for so long. Now that he's a "monster heel" again, it doesn't feel like it used to.
All in all, I think that Mr. Wight should keep wrestling for as long as he's able (and enjoys it). I wouldn't be surprised if he keeps working for WWE after his retirement from the ring, possibly as a trainer or something. I think that Paul Wight is the best big man worker of all time. He's just as big and intimidating as Andre is/was, although Big Show is able to do a lot of stuff that Andre couldn't do (flip over the ropes, etc). I hope he's able to work for as long as he wants, and I feel that he'll be over with live crowds (his size is ridiculous to see in person) for the rest of his days. I also hope we'll see him entertaining us for at least a few more years; I hope this isn't his last run, and I have a feeling that it's not.